Re: [RFC][PATCH 12/12] PM / r8169: Add simplified run-time PM support

Pavel Machek
2010-01-03T19:55:53Z

> > On notebooks, you can often use
> >
> > pavel@amd:/data/l/linux-msm/arch/arm/mach-msm$ cat
> > /proc/acpi/battery/BAT0/state
> > present: yes
> > capacity state: ok
> > charging state: charged
> > present rate: 0 mW
> > remaining capacity: 71830 mWh
> > present voltage: 16277 mV
> >
> > ...present rate is often usable-enough.
>
> Using /proc/acpi/battery/BAT1/state I measured the energy drawn in 10 minutes
> both with the network adapter in D0 and D3hot. The results were that with the
> network adapter in D0 the box drew 2476 mWh, while with the network adapter in
> D3hot it drew 2361 mWh. The difference is 115 mWh, or about 5% on this
> particular box.
>
> This means about 0.1 Wh in 10 minutes, so we can save about 0.6 Wh per hour.

Which means it saves 0.6W :-). Measuring power in Wh/h is
"interesting". Ok, that's consistent with my experiments, ethernet
transciever was around 1W... Thanks.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html